Blood sampler and an amplifier for use therewith

Abstract

An adapter 4 fitted in a tube holder 1 is composed of four flexible extensions 23 integral with the forward end of the adapter, and each extension includes a slanted portion 27 and a gripping portion 28 which may have a stopping lug 30 formed on the latter portion. An evacuated tube 3 is closed with a plug 15, which compresses an elastic sheath 12 covering the needle and is pierced by it together with the sheath, when inserted into the adapter 4 for taking a blood sample. The slanted portions 27 are elastically swingable outwardly to render the plug 15 coaxial with the holder 1. The gripping portions 28 are also capable of flexing following the swung slanted portions so that their forward ends are transitionally displaced centrifugally and then restored to their straight position to hold the plug 15 such that even if its outer diameter is considerably smaller than the inner diameter of the holder 1, the sampling needle 2 can penetrate the plug through its central zone and the plug is not "kicked back".

What is claimed is: 
     
       1. An adapter to be used with a blood sampler, the blood sampler including a tube holder, a double ended sampling needle having a first end extending through a top end of the holder, an elastic sheath fitted on and covering a second end of the double ended needle, an evacuated blood sample tube having a plug fitted in an open end of the tube, with the evacuated tube being adapted for insertion in a cylindrical body of the holder when a blood sample is to be taken, wherein during taking of a blood sample the elastic sheath is compressed in an axial direction so that the second end of the needle penetrates both the sheath and the plug so as to allow the blood sample to be sucked into the tube, the adapter being interposed between the holder and the evacuated blood sample tube, the adapter comprising: a cylindrical body having a circumferential outer dimension less than an inner dimension of the holder;   a plurality of flexible extensions integral with and protruding from a top end of the cylindrical body;   said flexible extensions extending axially of said body so as to surround the plug of an inserted blood sample tube;   each of said flexible extensions comprising:   a slanted portion inclined from the top end of the cylindrical body towards an axial center of the cylindrical body in a direction of the top end of the holder; and   a gripping portion integral with the slanted portion and extending parallel to the axial center of the cylindrical body, said plug having a top portion with an outside diameter greater than an outside diameter of said evacuated tube, said top portion being in frictional contact with said gripping portion when the needle penetrates the plug, said frictional contact preventing movement of the tube in a direction away from said top end.   
     
     
       2. An adapter as defined in claim 1, wherein the number of extensions is three or more, and the extensions are arranged at regular angular intervals around the cylindrical body of the adapter. 
     
     
       3. An adapter as defined in claim 2, wherein the adapter has its inner surface coated with a silicone agent or the like as a lubricant. 
     
     
       4. An adapter as defined in claim 1, wherein each extension further comprises a stopping lug integral with and protruding inwardly from the gripping portion such that the tube's plug held thereby is prevented from slipping off the gripping portions. 
     
     
       5. An adapter as defined in claim 4, wherein the number of the forward flexible extensions is three or more, and the extensions are disposed at regular angular intervals around the cylindrical body of the adapter, and have a width of 3 mm or less. 
     
     
       6. A blood sampler comprising: a tube holder,   a double ended sampling needle having a first end extending through top end of the holder, an elastic sheath fitted on and covering a second end of the needle,   an evacuated blood sample tube provided with an open end and a plug inserted therein the evacuated tube being adapted for insertion in the holder when a blood sample is to be taken, wherein during taking of the blood sample the elastic sheath is compressed in an axial direction so that the second end of the needle penetrates both the sheath and the plug so as to allow the blood sample to be sucked into the tube,   an adapter interposed between the holder and the evacuated blood sample tube, wherein the adapter comprises:   a cylindrical body having an outer dimension less than the inner dimension of the holder;   a plurality of flexible extensions integral with and protruding from a top end of the cylindrical body wherein the extensions extend axially of said body so as to surround the plug of an inserted blood sample tube, and wherein each of the flexible extensions has a slanted portion and a gripping portion, said gripping portion integral with and extending from the slanted portion toward said top end of said cylindrical body, the slanted portion is inclined radially inwardly from the top end of said cylindrical body towards a central axis of said cylindrical body in a direction of the top end of the holder, and the gripping portion extends from the slanted portion parallel to the central axis of said cylindrical body, said slanted portion frictionally engaging said plug so as to prevent movement of the tube in a direction away from said second end of the needle.   
     
     
       7. A blood sampler as defined in claim 6, wherein each extension further comprises a stopping lug integral with and protruding inwardly from the gripping portion such that the tube's plug held thereby is prevented from slipping off the gripping portions.